This invention converts an inexact, cut and try approach for closing the gaps between a Cathode Ray Tube ("CRT") and a bezel, into a precise, predetermined methodology. All four corners of a rectangular CRT are closed with precision, simultaneously, and without the need for shims. Equally important, the pressure applied to the bezel becomes controllable such that touch screen technology may be used in entertainment environments where reliable sealing against liquids is critical to safety.
The prior art discloses two philosophies of design in mounting a CRT inside a video display terminal cabinet, television, or entertainment machine so that it is aligned with a bezel and forms a liquid tight seal with the bezel. Each philosophy of design assumes that the CRT will be housed in an enclosure.
The first philosophy of design was to mount the CRT rigidly to the underside of the front panel, and to place the bezel in rigid mechanical connection in the face frame, with the underside of the bezel pressing tightly against the video display. This approach achieved tight sealing between the CRT and the bezel, but it required that all service be done through the rear panel.
The second approach was to have the front panel mounted to swing out of the way, for quick access to the front of the machine. This method had the great advantage that the machine can be serviced from the front. This approach allowed machines to then be placed side by side in long rows, such as in a casino, without the need for access through a rear panel.
The second approach made it impracticable to mount the CRT on the front panel. The weight of the CRT, the high voltage lines integral to the CRT operation, the need to avoid flexing wires, and the mechanical interference as the CRT swings with the front panel, all precluded mounting of the CRT to a moveable front panel. As a result, the CRT was then mounted in a metal frame which was then attached to a shelf within the cabinet.
The bezel, however, had to be mounted on the front moveable panel. Alignment of the bezel to the CRT when the front panel was closed, became a real problem. A large part of that problem was the need to align and firmly press the bezel against the CRT in order to achieve a liquid tight seal.
Initially, the industry solved the problem by simply placing safety glass or transparent plastic over the front panel to achieve sealing between the public and the video display. In this design, the bezel was under the glass, and the fact that there was poor alignment between the bezel and the CRT was not important because fluids would be deflected by the glass or transparent plastic.
Recently the industry adopted touch sensitive screens. In order for the public to touch the screen, the safety glass had to be eliminated from the design.
Again, the fact that the panel on the front was moveable then created the problem of aligning the video display with the bezel because any panel which swings or lifts out of the way will have many tolerances which lead to misalignment of the panel with respect to the cabinet. Therefore, a bezel mounted in the panel will likewise have misalignment with respect to the cabinet. And when the front panel is closed, the bezel, mounted to the front panel will not exactly close with uniform pressure onto the CRT.
This again presented the safety problem of achieving a liquid tight seal between the bezel and the fixed position video display. The solution in the industry was the labor intensive, cut and try approach of closing the front panel, pushing the CRT monitor from the rear of the panel, then trying to manually adjust the CRT monitor assembly to press, tightly but not too tightly, against the bezel, while bolting the monitor to the cabinet. Then opening and closing the front panel, and noting the gaps between the bezel and the CRT, and again, moving the video display monitor assembly, guessing at the right angle to adjust the CRT, loosening and tightening bolts on the monitor and between the monitor and the cabinet, and adding shims and washers to try to achieve the right fit.
Especially aggravating was that moving the entire monitor assembly would result in alignment at two of the corners of the CRT, but not, simultaneously at all four corners. Use of shims under the rear of the monitor might tilt the monitor to close the gap on the other 2 corners, but the very act of placing the shims would typically change the spacing of the first two corners.
In addition the CRT monitor typically has little clearance on the side for use of wrenches or pliers, thus making it yet more aggravating and difficult to make final adjustments to the tilt and lateral position of each of the four corners of the CRT, with reference to the edges of the bezel.
Again, when the machines are lined up side by side in a long row, there is no way to access the CRT monitor from the rear, and thus access must be through the front panel, yet when the front panel is closed, there is no way to adjust the bezel to make it press firmly, but not too firmly, onto the video display device.